Switch mechanism



' M. J. SANDIN SWITCH MECHANISM Filed Aug. 22 1922 2 Sheets-Sheet 1INVENTOR I -/\aur'ifs J. Sandin.

ATTORNEY July 31, 1928.

M. J. 'SANDIN swI'rcn uncnmsu Filed Aug. 22. 1922 2 Sheets-Sheet. 2

INVENTOR Nauriis J I Sandin- WITNESSES:

G/ATTORNEY Patented July 31, 1928.

UNITED STATES PATENT OFFICE.

MAURITS J. SANDIN, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTING-HOUSE ELECTRIO 8n MANUFACTURING COMPANY, A CORPORATION OF PENNSYL-VANIA.

SWITCH MECHANISM.

Application filed August 22, 1922. Serial No. 583,607.

My invention relates to switch mechanisms and particularly to thoseprovided with means for automatically operating them under predeterminedconditions.

One object of my invention is the provision, in a rotatable snap switch,of means for either manually or automatically effecting the operationthereof.

Another object of my invention is the of means, controlled by circuitconditions, for effecting an automatic operation of a rotatable snapswitch and for automatically effecting a resetting of the automaticmechanism after each actuation 1 thereof.

Still another object is to simplify the construction of snap switchesgenerally and to provide an improved form of operating mechanismtherefor.

A further object of my invention is the provision, in a rotatable snapswitch, of means whereby a single tension device may be employed toeffect a snap movement thereof upon either manual or automaticoperation. I I

It has been heretofore proposed to employ fusible members that arecontrolled by current in the circuit for permitting the switch to. openupon the occurrence of an overload, but none of the prior art of whichprovision I am aware has proposed to employ such a device in connectionwith a fully rotatable switch wherein a single tension device isemployed. l

As shown in the accompanying drawings,

Figure 1 is a view, partially in side elevation and partially insection, of a switch embodying my invention,

Fig. 2 is a view thereof partially in plan and partially in section, I

Fig. 3 is a bottom plan view thereof, I

Fig. 4 is a sectional plan view of certain of the switch parts shown inthe positions occupied thereby when the circuit through the switch iscompleted,

Fig. 5 is a similar view showing the position occupied by the said partswhen the circuit through the switch is broken,

Fig. 6 is a sectional view of the thermal device whichI employ, and

Fig. 7 is a detail view of one of the locking members.

I provide av base 7 to the outer side of which are secured stationarycontact members 8 and 9 that carry terminals 10 and 11, respectively.

A turn button 12 is secured to one end of a shaft 13 that extendsthrough the base. A ratchet wheel 15 is secured to the other end of theshaft 13. A bearing block 16 for the shaft 13 is set into a recess inthe outer sideof the base 7 to relieve the base of wear through theturning of the shaft.

A gear wheel 18 lies against the base 7 and is loosely supported by theshaft 13. :A camming disc 20 (Figs. 4 and 5) is rigidly secured to theshaft 13 and abuts against the outer side of the gear Wheel 18.

A" blade carrier 22 is loosely supported upon the shaft 13, forsupportinga blade or bridging member 23, being insulated therefrom-bywashers 25., A spring 26 engagesthe carrier 22 and a collar 27 that issecured to the shaft 13.

The blade carrier, at its inner side, has a lock plate 28 securedthereto by rivets 29 (Fig. 7). The plate 28 is provided with a slot 30in which slides an outwardly extending lug 31 of a camming ring 32 thatsurrounds the cam disc 20. The ring 32 is also provided with a radiallyextending portion 34 that serves as a stop member, as will behereinafter described.

The spring 26 is normally under tensionand the shaft 13 is held againstcounterclockwise movement by means of the ratchet wheel 15 and thespring-pressed pawl 15a (Fig. 3). f k

The blade carrier 22 is biased, through the tension of the spring 26, ina clockwise direction. Movement thereof, however, is prevented by reasonof the stop member 34 abutting against one of the stops 36 37, 38' and39 that project outwardly from the gear wheel 18. The slot 30 in theplate 28 holds the ring 32 against rotative movement relatively to theblade carrier 22.

The gear wheel 18 is prevented from turn- -1ng, by a gear wheel 41 thatis secured to a shaft 42 by fusible material, or solder, 43 (Fig. 6).cylindrical member 44 and thereby held The shaft 42 is cemented in a Iagainst turning. It will thus be seen that,

so long as the solder 43 holds, the blade carrier 22, and the blade 23thatis carried thereby, cannot move, unless the camming ring 32 is somoved as to carry the stop member '34 out of engagement with the stopmembers 36, 37, 38, 39, carried by the gear wheel 18.

In order to advance the switch to open position, the button 12 is turnedin a clockwise direction, thus increasing the tension of the spring androtating the camming plate 20, to move the cam ring 32' to the right(Fig. 4). This movement withdraws the lug 34 from engagement with thestop member 37 and permits the blade'carrier to be advanced by thespring 26. As the carrier advances, it carries with it the camming ring32, by reason of the engagement of the lug 31 thereof with the walls ofthe slot 30 in plate 28. This movement of the cam ring rotates it aboutthe cam plate that has just been given rotative movement through 90 are,as above explained, until it has reached substantially its formerposition relatively to the cam plate 20, at which time the stop 34thereof will make engagement with the stop 38 of the gear wheel 18. Thebridging member 23 then occupies its open position. Further turning ofthe button 12 will advance the camming ring into engagement with thestop members 39, 36 and 37, successively.

To effect an automatic" actuation of the switch, to break the circuit,when the parts are in the posit-ion shown in Figs. 1 and 4, it isnecessary to release the gear wheel 18 and permit it to rotate under theaction of the spring 26.

A resistance wire or heating element 46 is imbedded in the cementcontained in the cylinder 44 and is connected in series with the circuitthrough the switch. The resistance element 46 is an extension of thelead 47 and current flows therefrom, through the shaft 42, a terminalplate 48 (Fig. 2), shunt 49,- terminal 11, contact member 9, bridgingmember 23, and contact member 8 to the terminal 10.

Should the current in the circuit exceed a predetermined value, theheating element 46 will cause the solder 43 to soften, thus prmittingthe gear wheel 41 to rotate on the shaft 42, and releasing the gearwheel 18. The tension normally exerted by the spring 26 may now move thecarrier 22, and the gear wheel 18 in a clockwise direction.

The shaft 13 and the cam plate 20 carried thereby do not move, as .theyare biased in a counter clockwise direction, against the pawl 15a, bythe spring 26. Therefore, the camming ring 32, byreason of itsengagement with the slot of the plate 28, is rotated around the cam disc20 until the extension 34 thereof is in substantially radial alinementwith the shaft 13. At this period, the lug 31 is at the limit of itsradial path of movement, and moves into engagement with a raised stopmember 50 (Fig. 5) that is secured to the base 7, thus bringing theswitch parts to rest at open'position.

The solder will then become cooled and the gear wheel 41 again locks thegear wheel 18 against movement. The switch is now ready for anothermanual operation, by

means of the button 12, whereby the lug 31 of the cam ring 32 iswithdrawn from the stop member 50 and the extension 34 withdrawn fromthe stop 38 of the gear wheel '18. The tension of the spring 26 ismeanwhile being increased and the parts are snapped into -a positionwherein the cam ring extension 34 abuts against the lug 39, asheretofore described. The switch is now closed and ready for either anautomatic or a manual opening operation. A further automatic operationwill carry the lug 31 into engagement with the raised stop member 51disposed diametrically opposite.the member 50 (Figs. 1 and Thisautomatic movement is essentially the sameas the other automaticmovement above described.

The'lug 31 is never entirely out of engagement with the walls of theslot 30, and, at each of the two automatically released positions of theswitch, is in engagement both with one of the stops 50 and 51 and withthe slot- 30. The blade carrier 22 can never move without impartingrotative movement to the camming ring 32 and, owing to theinterengagement of the ring and the cam plate 20, all movements of thering are combined rotative and reciprocatory motions.

From the foregoing it will be seen that I provide a switch that may beautomatically moved to open position and that is automatically reset forfurther automatic operation. Also one wherein the manual operation ofthe switch may be freely effected without affecting the automaticmechanism and sufficient tension stored, when closing the switch, toinsure asnap movement thereof to open position when automaticallyreleased.

Various changes in detail and general arrangement may be made witlioutdeparting from the spirit and scope of the invention as defined by theaccompanying claims.

I claim as my invention:

1. The combination with a progressively rotatable switch member. of anactuating spring therefor, manually-operable means for placing thespring under tension to cause a snap movement of the said member, meansfor retarding the movement of the switch member, means responsive to thecurrent inllt the circuit whenever the circuit is closed by the switchmember for controlling the retarding means, and means whereby the energystored in the spring during manual operation of the switch member to oneposition causes movement of the said member to another position when theretarding means is actuated.

2. The combination with a rotatable snap switch and a tension device foractuating the same, of a normally stationary stop member for retardingthe movement of the switch, a stop member manually movable out ofengagement with the first named stop member 'member, a carrier for saito permit movement of the switch, a thermally-controlled member forpermitting movement of the first named stop member, under predeterminedconditions and a permanent stop member for arresting the last namedmovement at a predetermined point.

3. The combination with a rotatable switch member and a tension membertherefor, of means for storing energy in said tension member, a carrierfor said member, a stop member supported on the carrier, a gear wheelprovided with stop members in position to be engaged by the first namedstop member at predetermined positions of the said switch member, asecond gear wheel meshing with the first named gear wheel, andmeans'responsive to conditions in the' circuit for permitting the gearwheels to rotate.

4. The combination with a rotatable switch member and a tension membertherefor, means for storing energ in said tension member, a stop membersupported on the carrier, a gear wheel provided with stop members inposition to be engaged by the first named stop member at predeterminedpositions of the said switch member, a second gear wheel meshing withthe first named gear wheel, a fusible member for normally maintainingthe second gear wheel against movement, and a heating element in serieswith the switch for softening the fusible element to permit movement ofthe gear wheels.

5. The combination ,with a rotatable switch member and a tension membertherefor. means for storing energy in said tension member, a carrier forsaid member, a stop member supported on the carrier, a gear wheelprovided with stop members in position to be engaged bythe first namedstop member at predetermined positions of the said switch member, asecond gear wheel meshing with the first named gear wheel, meansresponsive to conditions in the circuit for permitting the gear wheelsto rotate, and means'limiting the movement of the said gear wheels afterthey have been released.

(3. The combination with a rotatable switch member of a tension membertherefor, means for storing energy in the tension member, a shaft forthe rotatable member, a cam member supported by the shaft and having alocking lug thereon, a movable member provided with stop members forengaging the said locking lug, a fusible memher for normally holding themovable member against movement, means controlled by conditions in thecircuit for rendering the fusible member ineffective to hold the saidmovable member in fixed position, and means for liniiting the movementofthe said movs )rin 'for the blade member, manually op- .erable means forplacing the spring under tension to cause a snap movement of the blademember, means for retarding the movement of the blade member, means atall times responsive to the current traversing the switch forcontrolling the retarding means, and means whereby the energy stored inthe spring during manual operation of the switch causes movement of theblade member to another position when the retardingmeans is actuated.

8. In a rotatable snap switch, a progressively rotatable blade member,contact members co-operating therewith, an actuating spring for theblade member, manually operable means for placing the spring undertension to cause a snap movement of the blade member, means forretarding the movement of the blade member, means at all timesresponsive to the thermal action of the current traversing the switchfor controlling the retarding means, and means whereby the energy storedin the spring during manual operation of the switch causes movement ofthe blade member to another position when the retarding means isactuated.

9. Switch mechanism comprising a contact member, a switch member movableinto engagement with the contact member, means including a progressivelyrotatable shaft for operating the switch, andmeans manually operable toretaining position for releasably releasing the switch in engagementwith the contact member, the said means being current responsive forreleasing the said switch member. v

10. The combination with a rotatable snap switch and a tension devicefor actuating the same, of' a normally stationary stop member forretarding the movement of the switch, a stop member manually movable outof engagement with the first named stop member to permit movement of theswitch, a thermally-controlled member for permitting movement of thefirst named stop member under predetermined conditions and a permanentstop member for arresting movement of the switch at a predeterminedpoint. I.

11. The combination with a rotatable snap switch and a tension devicefor actuating the same, of a normally stationary stop member forretarding the movement of the switch, a stop member manually movable outof engagementwith the first named stop member to permit movement of theswitch, a curr nt responsive member for permitting movement of the firstnamed stop member under predetermined conditions and a permanent stopmember for arresting move ment of the switch at a predetermined point.

12. The combination with a rotatable snap switch and a tension devicefor actuating the same, of a pair of relatively movable stop members forsuccessively retarding the morement of the switch, a stop device for theswitch manually movable out of engagement with the said stop members topermit movement of the switch, and a current responsive device forpermitting relative movement of the first said stop members to releasethe said stop device.

13. The combination with a snap switch and a tension device foractuating it,'of a pair of cooperating movable stop members .forreleasably retarding movement of the switch, one of the said membersbeing manually operable to releasing position with respect to the otherto permit movement of the switch and the other of the said members beingcurrent responsive and movable to releasing position with respect to theother to permit movement of the switch.

.In testimony whereof, I have hereunto subscribed my name this 10th dayof August 1922.

MAURITS J. SANDIN.

